The Texas Mile is an annual three-day racing event held on an airport runway 90 miles south of San Antonio. The rules are simple: more than 200 amateur racers in 11 different classes have a one-mile chance over the course of three days to see how fast they can go.

The car cost roughly $200,000 new in 2007, plus thousands of dollars Holt spent with Underground Racing, a high-performance tuning outfit in Charlotte, N.C., beefing it up with engine extras to give it super-fast capabilities.

That price tag is out of reach of most Americans, but speed doesn't have to cost a fortune. The Nissan 370Z, Ford Mustang GT500 and Infiniti G37, for instance, each cost less than $50,000 — and they all get to 60 miles per hour in under six seconds.

To compile our list of the fastest cars under $50,000, we combed through zero-to-60 mph times for all likely performance coupes, sedans and roadsters (SUVs and trucks didn't qualify when it came to competing with these cars on speed) sold in the U.S. that cost under $50,000. The vehicles with the fastest times made our list. Zero-to-60 times were provided by the manufacturers or by Kelley Blue Book. Sport packages that may have decreased acceleration times but pushed the MSRP over $50,000 were not considered.

This can be a tough combination. That's because speed is achieved through costly turboboosters and torque and by lightweight carbon-fiber body panels and aluminum frames. The aluminum frame of the Audi TTS, for example, is 48 percent lighter than a steel frame of identical size. Other components, such as carbon fiber spoilers, ceramic brakes and finely tuned, hand-built engines are considerably more expensive than standard features. That's where the delicate balance of price vs. power comes in.

BMW has several models on our list. The Munich-based automaker prides itself on its high-performance engineering and driver-oriented design, found, for example, in the $46,000 Z4, $40,600 335i and $36,050 135i.

A base version of the 335i sedan has a 3.0-liter, 300-horsepower, turbo-charged engine that will go from zero to 60 mph in 5.6 seconds (5.7 seconds with automatic transmission), with a top speed of 150 mph. The car makes things easy for drivers who actually enjoy the act of driving, using dynamic stability control and traction control to monitor the car around corners and through slick patches, with an on-board computer that shows oil levels, spark-plug status and remaining travel range.

The 135i is less expensive than its 3-Series counterpart, and smaller. Its size allows BMW to charge less than the 335i and makes the car faster. Jake Fisher, who has tested hundreds of cars for Consumer Reports, says that with the right driver, the 135i can even hold its own against more expensive sports coupes, like BMW's M3. Indeed the 135i does zero to 60 in 5 seconds (5.1 seconds with the manual), thanks to a turbo-boosted, 6-cylinder, 300-horsepower engine. Top speed is 131 mph.

Foreign-made cars — including the Porsche Boxster, Infiniti G37, Lexus IS and BMW Z4 — dominate our list, but three American-made cars top it: Ford's $48,645 Mustang GT500, Dodge's $41,230 Challenger SRT8 and Chevy's $30,945 Camaro SS go from zero to 60 miles per hour in 4.3, 4.9 and 4.6 seconds, respectively. And the Challenger even has a zero-to-60 timer right on the dashboard.

Ford's GT500 packs a supercharged 5.4-liter V8 engine with 540 horsepower and 510 pound feet of torque. The SS also has a V8, but this one's even bigger: a 6.2-liter, 426-horsepower engine. Both cars have standard 6-speed manual transmissions. ”

These autos embody the legacy of American muscle cars, says Mike Caudill, an automotive expert for NADA Guides. But of the three, the Mustang has been around the longest — with continuous production since it debuted came out in 1964. (The Challenger and Camaro both temporarily left the market, were redesigned and then reissued.)

Ford sold 5,145 Mustangs in the U.S. last month, down 33 percent from April 2009 but up 20 percent for the year to date. Dodge sold 3,713 Challengers in April, up 42 percent from April 2009 and down just 2 percent for the year to date. Chevy sold 9,150 Camaros last month (the car hasn't been on sale long enough for an accurate year-over-year comparison.) The relatively strong sales show that even during tough times in the auto industry, niche segments like fast cars that aren't extremely expensive, still have a loyal audience.